diff --git a/libs/ardour/control_protocol_manager.cc b/libs/ardour/control_protocol_manager.cc
index b95dc1cbca..6a7bdfb3cb 100644
--- a/libs/ardour/control_protocol_manager.cc
+++ b/libs/ardour/control_protocol_manager.cc
@@ -172,6 +172,7 @@ ControlProtocolManager::drop_protocols ()
 		if ((*p)->protocol) {
 			(*p)->requested = true;
 			(*p)->protocol = 0;
+			ProtocolStatusChange (*p); /* EMIT SIGNAL */
 		}
 	}
 }